The problem of discomfort glare of lamps is known in the art. US2010117100, for instance, describes a light-emitting module which makes it difficult to sense glare and which suppresses the temperature rise of light-emitting diode chips and has a cost advantage. The light-emitting module is provided with a base body formed with a non-metallic member having a thermal conductivity of 1 W/mk or less. In the base body, a plurality of LED chips are spaced 10 to 30 mm apart from each other, and their junction temperature when they are normally lit is preferably set at 90° C. or less. A translucent sealing member covering an area between the adjacent light-emitting diode chips is provided.
US20130107530 discloses a lighting system comprising a plurality of lighting units in a plurality of grids, with a shortest distance between nearest neighbor grids of about 20 mm.